Electric heater.



F. KUHN & P. E. SHAILOR.

ELECTRIC HEATER.

APPLICATION FILED r1113. 6, 1914.

1,107,323, I Patented Au .18,1914

UNITED STATES PATENT OFFICE. v

FRANK KUHN AND FRANK E. SHAIIIOR, OF DETROIT, MICHIGAN; SAID SHAILOR I Ai -IGNOR TO SAID KUHN.

" ELECTRIC HEATER.

To all whom z'tmay concern:

Be it known that we, FRANK KUHN and FRANK E. SHAILoR, citizens of the United States of 'America, residing at Detroit, in the county of WVayne and State of Michigan, have invented certain new and useful Improvements in Electric Heaters, of which the following is a specification, reference being had therein to the accompanying drawings. v

The invention relates to electric heaters of .the type in'which the heat is distributed by radiation from a nakedresistor, and the invention comprises various features of construction as hereinafter set forth. I

In the drawings: Figure 1 IS a perspectlve view of the heater; Fig. 2 is a cross section showing the manner of forming the protecting grid and of suspending the resistor; Fig. 3 is a plan view of a section of the heater;- and Fig. 4 is a cross section showing the arrangement of terminal contacts.

A is a sheet metal casing having an annul'ar section and a series of cross bars B formed integral therewith and twisted-to'expose the edge only in the open area. Within this casing is supported a ring G on which the resistor is'mounted. This ring is preferably formed of a strip of mica C ha'ving metallic binding strips C of U-shaped section embracing the edges of the mica. A series of apertures D are formed in the center of the-strip, which is then bent into circular form. The resistor E, preferably in the form of a helical coil, is then passed across the ring, being threaded through the apertures D as shown in Fig. 3, and if desired, an intermediate cross strip F similar A in construction to the strip C maybe used for supporting the center of the coils.

The ring G is supported within the casing A, preferably by providing the latter with inwardly-extending brackets .G secured thereto by spot-welding or otherwise, and attached to the inner ring by screws or other securing devices H. This will support the ring 0 and the resistor beneath the grid I formed by the cross bais B, thereby protectmg the resistor 61 short circuiting; A further protection ay be formed by rods I extending transverse to the bars B and engaging notches I therein, the edges of which are clenched to retain, the rods. If desired, here maybe also a protecting grid below thgesistor, formed by cross bars J secured Specification of Letters 2mm. Patented Aug. 18, 1914:. Application filed. February 6, 1914. Serial No. 816,876.

.to the metallic edge strips C on the lower side of the ring.

The casing A may be supported upon a suitable stand, such as K, which is shown as having a plate or table with depending legs L on opposite sides thereof. Standards M upon opposite sides of this table and extending upward therefrom, are secured to the ring A by suitable means, such as screws N which, when detached, permit of removing the unit. The terminals 0 are mounted upon a bracket member P secured to the ring A and having a guard-plate Q extending over the terminals to protect them from ln ury.

The construction described is one which can be cheaply manufactured, as the outer case A with :he integral cross bars B may be formed fr m a cupped blank of sheet metal, with the metal between the cross bars cut away. The inner ring C is also cheaply manufactured and easily assembled with the resistor and the. casing A.

"What we claim as our invention is 1. An electrical heater, comprising an annular casing, a ring within said casing formed of a strip of insulatingmaterial havin metallic-bound edges and a series of central apertures, a resistor threaded through said apertures and extending across said ring, and means for supporting the inner ring from the outer ring.

2. An electrical heater, comprising an annular sheet metal casing having integral cross-bars twisted to expose their edges in the open area, transversely-extending rods engaging notched bearings in said crOSS bars and havlng a clench engagement therewith, a rin formed of insular material supported within said outer ring and beneath the cross bars thereof, and a resistor threaded through apertures in said insulator ring and extend ing thereacross.

3. An electrical heater, comprising a sheet metal cupped casing cut away to form a series of cross-bars connecting the outer ring, said cross bars being twisted to expose the edge only in the open area, a series of cross-bars engaging notched bearings in the integral cross-bars and having a clench engagement therewith, an inner ring formed of a strip of insulator material having metallic-bound edges and a series of central apertures, a resistor threaded through said apertures and extending across the ring, a

bracket secured to the outer ring and connected to the metallic portion of the inner ring to support the same, and a series of cross-bars extending across the inner ring beneath said resistor.

v d. An electrical heater, comprisin a cupped sheet metal casing cut away to 01m spaced Cross-bars twisted to expose their edges only in theopen area, a. series of rods extending transversely to said cross bars and having a cleneh engagement With notched bearings therein, an inner ring formed of insulator material, a naked resistor extending across said inner ring and supported thereon, terminal contacts, and a, bracket 15 seeured to said outer ring to which said ternnnal contacts are secured said bracket being provided with a guard plate extending over the contacts.

In testimony whereof we afiix our signa- 2U Copies 0! this patent may be obtained for five cents each, by addressing the Commissionenot Pate" Washington, I). C. 

